Stacker



Feb. 23 1926.

Y c. PEARSON 2 Sheets-Sheet 1 gneaj March a, 1924 .Ewenjlar.

Feb. 23 y 1926.

C. PEARSON STACKER M w 6 Q Mr 5 m J w a Uhazieflle Fetcnted Fell. 23, lfil' iti,

ill illi STATES arent CHARLES IPEARSOBT, GT1. CHICAGO, ILLINOIS, ASSIGNOR TO INTERNATIONAL HAR- VEI'BTER COMPANY, OF CHICAGO, ILLINOIS, A. GGRPORATION OF NEW JERSEY.

STACKER.

Application filed March 8, 1924. Serial No. 697,727.

may concern.- that l, Crmnnns PEARSON,

T (13 a'elzom it lie it known a citizen of the Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Stackers, of which the following is a full, clear, and exact lifting frame so that there will be a wide.

range of adjustment affording a high lift when required andpositive operation of the extensible head without possibility of binding. This principal, and other minor objects, are attained by employment of structnre having improved mechanism for controlling the extension and retraction of the stacker head, which structure is characterized by having means for varying the degree of the extension given the sliding arms carrying the stacker head and separate and independent means for positively retracting the arms as the lifting frame and stacker head are lowered.

The invention accordingly resides in the organization and details of construction, or equivalents thereof, hereinafter described and claimed.

Referring to the drawings,

Fig. 1 is a side view of a stacker embodying the invention showing the lifting frame in its lowered position;

Fig. 2 is a side View of the stacker with the liftin frame elevated and the stacker t head extended; and

3 is a plan view or the stacker with the stacker head omitted.

The improved stacker comprises a base composed of parallel sidecsills and 11 connected at their ends by crosspieces 12 and 1S and by an intermediate cross piece at the top by a transverse member lo and are suitably braced as by thediagonally United States, residing at extending side braces 17 and 18. At points spaced some distance inwardly from the vertical posts there are secured to the inner sides of the side sills short vertical standards 19 on which are pivoted the main lifting arms 20 of the vertically swinging lifting frame, Thesearms are pivoted on the outer sides of standards 19mm are located directly above the sills, the front ends of which are bevelled off, as at 21., to permit the outer ends of the lifting arms to come close to the ground when the frame'is down.

Slidable extension arms 22 are mounted on the main lifting arms 20 on which they are guided and held in position by a yoke piece 28 secured to the front endsof thearms 20 and by in'ackets 2 lsecured to the rear ends of the extension arms 7 22 and extending below the main arms 20 where they carry anti-friction rollers 25 which travel on the under side of arms 20. These extension arms carry the stacker head 26, which may be of any preferred construction. ary lifting or radius arms 27 are pivoted on. the base frame at-points forwar dand above the axis of the lifting frame and prefcrably on the upper ends of the corner posts 15 asshown in Figs. 1 and 2. The secondaryarms 27 extend toward the lifting frame, as shown in the drawings, and links 28, each composed of a pair of spaced parallel bars pivoted on opposite sides of the ends of the arms 27 and to the main lifting arms 20 towardtheir outer ends, as seen in Fig. 1, serve to pivotally connect the main arms 20 and secondary lifting arms 27 so that they swing in unison as the lifting frame is raised and lowered. Lifting arms'2oand 27, together with the connecting links 28, provide a construction which becomes locked against further movement when the secondary arms 27 reach asnbsta-ntially vertical lifting frame toward the stack is auto inatically stopped by the links 28 when the parts reach positions seen in Fig. 2'. This construction eliminates the buffer frame heretofore usually employed to limit the upper swing of the lifting frame. The secondary or radius arms 27 control the extension of the slidable arms 22 and for this purpose are connectedto the slidable arms by adjustable coupling means comprising sleeves 29 which are movable from p int to point al ng t e rms 27 and n- Second- 29 for re ulatini the de ree of extension given the stacker head, consisting in this instance of a series of spaced apertures 32 adapted to register with corresponding aper tures in the sleeves 29 which can be held III in adjusted position at any point in the length of arms 27 by a pin 33 passed through the registering apertures in the arms and sleeves. In connection with the bars composing the links 28 which connect the main and secondary lifting arms there is provided a spring tension device com-' posed of contractilesprings 34 positioned between the arms of links 28 and attached thereto at their upper ends by pivoted staple members 34? while their opposite ends are attached to short links 35pivoted on bracket members secured to the main lifting arms 20 and extending above the slidable ektension arms 22, as clearly shown in Fig. 1, the pivot point of links 35 being just above that of the links 28 to arms 20.

The organization comprising the main and secondary lifting arms and the spring cushion means cooperating therewith, which has just been described, does not form the subject matter of the present application but is described and claimed in a copending application, Serial'No. 639,243, filed May 16, 1923.

As means for applying power to raise and lower the'lifting frame, there is provided a vertically swinging jib composed of upwardly converging beams 37 which are .pivoted on the side sills to their lower ends and rigidly connected together at their upper ends. The jib has its outer end connected to the ends of the main lifting arms 20 by means of lifting rods 38 which are pivoted to the end of the jib members 37 and to the outer ends of the lifting arms 20. Between theouter ends of the jib members ,37 there is journalcd a sheave 39, and twin sheaves 4-0 are journaled centrally of the transverse bar 16 in alignment therewith and with another sheave 4E1 journaled in the swiveled bracket on thebase of the frame. An operating cable 42 passes over the several sheaves and is'attached to the jib, est ending then to the source of power in the usual manner. The construction so far described provides forraising and lowering the lifting frame and for variable extension of the stacker head, if desired, but it has been found in' practice thatthe weight of the stacker head and extension arms alone cannot be depended upon to cause" falling back or retraction of the es:-

tension arms 22 whenthel ifting frame is being lowered, and, in order to provide positive means for retracting the extensible sliding arms 22 during the lowering of the lifting frame,'there are provided fixed brackets 43 each consistingpreferably of a pair of upwardly and inwardly inclined converging bars connected at their outer ends and secured to the vertical portion and braces of the base frame near the upper ends of the corner posts 15. These brackets 43 provide properly located points of attachment for flexible retracting connections, such as the lengths of chain 44-, which connect the brackets 43 with the upper ends of the arms 31 on the slidable extension arms 22.

The relative positions of the points of attachment of chains 4H to brackets 43 and to arms 81 are such that these two points approach each other as the lifting frame rises, and draw apart as the frame is lowered, the chain length and relation of attaching points being such as to compel return of the extension arms to their extreme retracted position, if they have been given any extension during the raising of the lifting frame.

The operation of the stacker is effected through the cable =12 in well known manner, the improved construction above described functioning as follows:

lVh'en the lifting frame is in lowered position, as in Fig. 1, the relation of parts is such that springs 34 are under tension and exert a lifting action on arms 20. If cable 42 is now pulled, the jib 37 will begin its swinging, andlifting rods 38 will pull on lifting arms 20, the assistance of springs 34.- causing the lifting movement to start without straining and with application of less power than heretofore required in similar structures. As lifting progresses, it will be obvious that the springs .34 will become slack during an intermediate period in the lifting operation, and, as the main and secondary arms continue to rise, the links 28 connecting them swing in such a way that the upper ends of springs 34 are shifted from one side .of their points of connection to arms 20 to the other side thereof, and, as the end of the raising movement is reached,

the springs are again placed under tension,

as in Fig. 2, and-the end of the upward swing is also cushioned, the tension of the springs then acting to cause recoil of the lifting frame, tiereby initiating the downward swin thereof. During the lifting and lowering operation just referred to, it was assumed that sleeves 29 were pinned. in the apertures nearest the pivots of arms 27.

ljnder those conditions,'there was no extension of arms 22 and no additional lift given the stacker head as chains remain slack. hen it is desired to increase the height of the lift, the sleeves 29 are pinned, usually by successive stages, int-he several apertures 32 of the arms 27 to follow the rising stack,

and, for purposes of illustration, the sleeves slack. Upon return movement, if the extension arms 22 stick or bind and fail to move down on the arms 20 of their own weight, the chains as, which soon will become taut, will exert a pull on the lower ends of these arms and positively force their return to the initial retracted position. It will be evident that the degree of extension given the arms 22 will be governed by adjustment of sleeves 29 on the arms 27 and that the extension given will become greater as the sleeves are pinned in the apertures farthest from the pivot of the arms 27.

The above description will make it clear that a simple, strong and easily operated construction has been devised in which the height of lift can be quickly and easily adjusted within a considerable range and that both the extension and retraction of the stacker head are positively governed, efficient operation being, therefore, made certain. lVhile the preferred form of the novel construction constituting the invention has been described, it will be understood that considerable variation is possible without departing from the scope of the invention as defined in the following claims.

\Vhat is claimed as new is:

1. The combination of a normally stationary base frame, a lifting frame pivoted thereon, said frame comprising a main lift ing arm and an extension arm, means for swinging the lifting frame upwardly and for simultaneously causing projection of the extension arm, and means independent of said swinging means and having one end connected to means fixed relative to the base frame for effecting retraction of the extension arm on downward movement.

The combination of a base frame, a lifting frame pivoted thereon, said frame comprising a main lifting arm and an extension arm, means for swinging the lifting frame, a secondary lifting arm pivoted on the base frame on an axis above that of the lifting frame, means causing the lifting frame and secondary arm to swing in unison, means actuated through upward movement of the secondary arm for causing projection of the extension arm, and independent m an f r. ef ec i g retrae en the sion a m on downward movement of the lifting frame.

3. The combination of a base frame, a lifting frame pivoted thereon, said frame comprising a main lifting arm and an extension arm, means for swingingthe lifting frame, a secondary lifting arm pivoted on the base frame on an axis above that of the lifting frame, means causing the lifting frame and secondary arm to swing in unison, means actuated throu 'h upward movement of the secondary arm for causing projection of the extension arm, and independent means, comprising a flexible connection between the extension arm and a fixed point of attachment-on base frame, for effecting retraction of the extension arm on clownward movement of the lifting frame.

i. The combination of a base frame, a lifting frame pivoted thereon, said frame comprising a main lifting arm and an extension arm, means for swinging the lifting frame, a secondary lifting arm pivoted on the base frame forwardly of the lifting frame on an axis parallel with and above the axis of said frame, a link pivotally connecting the main lifting arm to the secondary arm, a flexible element connecting the lower end of the extension arm to the secondary arm, and a second flexible element connecting the lower end of the extension arn'r with a fixed point of attachment adjacent the pivot of the secondary arm.

5. The combination of a base frame, a

lifting frame pivoted thereon, said frame comprising a main lifting arm and a slidable extension arm, means for swinging tli lifting frame, a secondary lifting arm pivoted on the base frame forwardly of the lifting frame, and flexible connections between the lower portion of the extension arm and the secondary arm and between the extension arm and a forward point of attachment on the base frame.

6. The combination of a base frame, a lifting frame pivoted thereon, said frame comprising a main lifting arm and a slidable extension arm, means for swinging the lifting frame, a secondarylifting arm pivoted on the base frame forwardly of the lifting frame, a flexible connection between the lower portion of the extension arm and the secondary arm including a member adjustable from point to point along said arm, and a second flexible connection between the extension arm and a forward point of attachment on the base frame.

7. A hay stacker including a normally stanally slidable relative thereto, ,n1eans for swlnging the lifting frame upwardly, a de viee for causing projection of the extension arm, and means independent of said swinging means and having one end anchored at a point which is fixed relative to said base frame for effecting retraction of the extension arm on downward movement thereof.

8. A hay stacker comprising a base, a lifting frame, an extension arm, the lifting frame being swingable from a loading position to an unloading position, means for swinging said lifting frame, and lost motion connecting means independent of. said swinging means for effecting retraction of the extension arm on downward movement of the lifting frame to loading position, said lost motion means having one end anchored to said extension arm and its other end anchored at a point whichis fixed relative to said base frame.

9. A hay stacker comprising a base frame, a lifting frame pivoted thereon, said frame comprising a mainlifting arm and an extension arm, means for swinging the lifting frame upwardly, means for causing the projection of the lifting arm, and a device independent of said swinging means and wholly operativ'ely interposed between said base frame and said extension arm for effecting retraction of the extension arm as the lifting frame moves downwardly.

In testimony whereof I affix my si nature.

CHARLES PEAasoN. 

